Andrew Gabriel wrote:

In article ,
The Natural Philosopher writes:

Peter Morrill wrote:


I have just finished a brick wall around my front garden. I have ordered
some natural sandstone copings, with wrought iron railings to go on top.
Could anyone please advise me on the best mortar mix (and any other
hints) to lay the sandstone on top of the brickwork. Being on a main
road with heavy pedestrian traffic, I want the copings to be secure.
Many thanks
Peter Morrill

Mmm. Pretty much any mix will probably do. I have laid bricks and stones
with wildly varyg mixes from 2:1 to 20:1 sand/cement.

The porosity goes down and brittleness goes up with more cement.

Adding hydrated lime reduces the brittleness and makes a really nice mortar.

Try 1:1:6 lime/cement/sand.

Or 3:1 sand/cement.


I would add some PVA to the mortar used for capping on a wall.
Helps stop it lifting off. I use about a teaspoon of PVA per
2 shovel loads of sand, mixed into the water. (Actually, much
easier to mix the water into the PVA in equal quantities at
first, and then add more water to dilute it down.) There's a
waterproof PVA which I happen to use because I have it, but
I don't know if it makes any difference over the ordinary PVA.


I found that the lime addition - which I really did to get a color and
texture - seemd to make the mortar stickier. Have you tried both? I'd be
interested to hear the difference. I dis use a bit of PVA in osme mixes
but to nbe hinest, I couldn;t tell teh difference, and irrsepectve if
what I used and how dry the mixture was, it all seemed to cure bloody
solid in the end.